Some Parts of Cars Can Be Made of Titanium Alloy
Nowadays, the progress of automotive materials is tightly around the theme of environmental protection, energy saving, safety, comfort and low cost, so the development of automotive materials is also more diverse, the most prominent and urgent of which is lightweight, compared with 10 years ago, the structure of automotive materials has changed significantly. The use of new materials and advanced manufacturing processes complement each other, the automotive industry is trying to develop new manufacturing processes, to update the traditional industry. Lightweight materials, in addition to the traditional aluminum and magnesium, titanium and composite materials are also excellent lightweight materials, but the current price is still higher, with the progress of technology and the increase in the amount, the price will slowly decline.
Titanium, with its lightweight, high strength and other excellent performance, which has long been favored by manufacturers, the application of titanium in racing cars has nearly 40 years of history, the current racing cars and sports cars are all use titanium. The United States has produced racing titanium alloy intake valve, exhaust valve, valve guard and rod, also the other accessories, Japan's first use of titanium car is Nissan "382”.
● Engine Connecting Rod
When the car is driving at full speed, most of the friction loss of the engine is caused by the piston connecting rod components (piston, piston pin and connecting rod), its quality is reduced, the fuel utilization rate is greatly improved, the displacement is also reduced accordingly. After the use of titanium to manufacture this part, compared with the previous aluminum alloy parts, the engine drive temperature increased, the temperature of use is higher. The connecting rod should have high strength and fatigue resistance, rigidity and wear resistance, so titanium alloy and composite materials have become the suitable materials for the manufacture of connecting rods, to realize the lightweight piston and piston pin, thus the noise and vibration have been greatly reduced, and the performance of the engine has been improved. Due to the piston pin strength, wear resistance, rigidity, heat resistance and other high requirements, it should choose a titanium alloy containing more titanium-aluminum compounds. Engine speed is increasing, valves, gears, etc. are also best prepared with titanium alloy, for titanium alloy has excellent creep resistance and oxidation resistance, composite titanium and AITi alloy is the best material for the preparation of exhaust valves, Ti Gr.5 alloy is the best material for the preparation of exhaust valves.
In 1956, Volkswagen built a small car for exhibition, the body of which is all made of titanium. From that time, the COO car is equipped with a 300mL cylinder engine, the net weight of the car is only 290 kg,is made of lightweight materials such as Al, Mg, Ti resin matrix composites, fuel efficiency of 100 km/L.In 1990, the connecting rod of Honda Motor Company's NSX V﹣6 racing car was made of Ti﹣3Al﹣2.5 V﹣Si﹣RE alloy, an alloy that can be cut at high speed; in 1994, the connecting rod of the 3.0L 24﹣valve V-6 engine of the NSX racing car produced by the company was forged with titanium alloy. The V12 engine of the Italian Ferrari 2003 En20 supercar uses titanium alloy connecting rods to greatly enhance maneuverability,and the boost speed can reach 62 km/h in 3.9s. The connecting rods of Porsche cars are also made of titanium.
Valve seat is made of titanium alloy, widely used in racing cars, multi-purpose Ti-6Al-4V alloy manufacturing, but also useful Ti-5Al-2Cr-1Fe alloy manufacturing, valve seat shape is simple,easy to machine, the cost is also low,but do not have to special surface treatment, its quality is 10 g ~ 12 g lighter than steel.The Japanese automobile factory used Ti﹣5Al﹣2Cr﹣1Fe alloy to make crankshafts and some other parts,and Ti-6Al-4V alloy to make rocker arms,valve springs and lower bolts of connecting rods.According to Japanese experience, automotive power valves use 0.8 kg ~ 0.9 kg titanium, equivalent to the effect of weight loss of 20kg.
● Exhaust Pipe and Muffler
The amount of titanium in the exhaust pipe of the car is large.In the past, exhaust pipes and mufflers used ordinary steel, aluminum alloy, fiber reinforced plastic (FRP) and so on.Exhaust temperature>400℃, the heat resistance of titanium is much higher than that of aluminum alloy,and the specific strength is higher than that of steel.The manufacture of exhaust pipes and mufflers must go through bending, cold pressing and other forming processing, requiring good cold forming performance of the material.In addition, the muffler is a component of the car body, made of titanium alloy is more innovative and stylish.Titanium exhaust pipe shown in below.
